Paul and Joanne met in the early '50s.

Paul and Joanne met when they were both in the Broadway play Picnic in 1953. At the time, Paul had been married to his first wife, Jackie Witte, since 1949. He began having an affair with his co-star, though he and Witte remained married for several more years. The couple had three children together: Scott, Susan, and Stephanie Newman.

In 1958, they divorced, and Paul wed Joanne. They were married for 50 years until his death in 2008 at age 83. They also welcomed three children together: Melissa and her sisters, Nell and Claire Newman. Today, Joanne is 93 years old.

In addition to sharing their lives, Paul and Joanne worked together. They co-starred in movies including The Long Hot Summer, Paris Blues, A New Kind of Love, and Winning. He also directed her in some of his films, including his directorial debut Rachel, Rachel.

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Melissa found love letters Paul wrote early in their relationship.

Melissa told Fox News Digital shared that she found letters her father had written to her mother while she was looking through the attic at her parents' home in Westport, Connecticut.

"We’d gone through ripped bags. I remember right before one was about to be thrown out, I reached in—there were moths and dead mice everywhere… And I found the first 10 letters my dad ever wrote to my mom," Melissa recalled. "It was this close to being thrown away."

She added of Paul's love letters, "I always say, ‘People, read the things that my dad wrote to my mom… [and] take notes, man.' This is how you woo somebody. And it’s just so obvious that he was just [hit] upside the head. He fell for her so hard."

Some were too risqué to be included in the book.

Melissa explained that while excerpts of the letters are featured in Head Over Heels, she decided that their entire contents weren't appropriate.

"I would read the letters and just go, ‘Oh, this is so sweet. This should go in the book,'" she said. "And then I would be reading on, and then I’d go, 'Ooh, Dad, I can’t put this in the book!'"

The 62-year-old described the letters as "naughty" and "bawdy," but clarified that they are "not smutty." She continued, "I would get to a point in the letter where I’d say, ‘I can’t print this.' But… It was charming."

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Paul opened up about their sex life in his own memoir.

Paul's memoir, Paul Newman: The Extraordinary Life of An Ordinary Man, was published posthumously in 2022 and is based on an oral history of his life that he began working on in the 1980s. In those conversations, he opened up about his sex life with Woodward and explained how she changed him.

"Joanne gave birth to a sexual creature," Paul explained (via People). "We left a trail of lust all over the place. Hotels and public parks and Hertz Rent-A-Cars." He added, "I went from being not much of a sexual threat to something else entirely."

The book also tells the story of a room Joanne set up off of the primary bedroom in their Beverly Hills home.

"'I call it the [Expletive] Hut,' she said proudly," Paul recalled in his memoir. "It had been done with such affection and delight. Even if my kids came over, we'd go into the [Expletive] Hut several nights a week and just be intimate and noisy and ribald."

Melissa called her mom a "sex bomb."

Melissa told Fox News Digital that she was not surprised to learn about the "[Expletive] Hut."

"It made perfect sense," she said. "And I was like, ‘You go, Mom!’ My mom was just a free spirit. She was her own powerful force… She did it all. And evidently, she was a sex bomb at the same time." She also writes in her book that her parents' bedroom door had "comically large bolts" that "functioned like an airlock."

Melissa also shared that, despite their obvious chemistry, her parents' marriage could be "messy" just like anyone else's. But, they stuck together through hard times.

"They were artistic compatriots, they were lovers and they were fighters," she said. "It was this ribbon, this cord that just tied them together despite everything. There was no way they could leave even when they wanted to… It was like a bungee cord. They’d always come back together."

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